Function
Bifunctional inositol kinase that acts in concert with the IP6K kinases to synthesize the diphosphate group-containing inositol pyrophosphates diphosphoinositol pentakisphosphate, PP-InsP5, and bis-diphosphoinositol tetrakisphosphate, (PP)2-InsP4. PP-InsP5 and (PP)2-InsP4, also respectively called InsP7 and InsP8, may regulate a variety of cellular processes, including apoptosis, vesicle trafficking, cytoskeletal dynamics, and exocytosis. Phosphorylates inositol hexakisphosphate (InsP6) at positions 1 or 3 to produce PP-InsP5 which is in turn phosphorylated by IP6Ks to produce (PP)2-InsP4. Alternatively, phosphorylates at position 1 or 3 PP-InsP5, produced by IP6Ks from InsP6, to produce (PP)2-InsP4.
Sequence
MSYTELESGYQDISQQHQQQNPHQSQPQQRVGFYLGLQDGNGDTDFGDSNDGMDSDTSTSSSNSKQVVVGICAMAKKTQSKPMKEILTRLGEFEFIKLVTFEENVILREPVQNWPTCDCLVSFHSKGFPLEKAIEYAQLRNPFVLNNLHMQYDIQDRRRVYAILEKEGIEIPRYAVLDRDSPDPKHHELIESEDHVEVNGITFNKPFVEKPVSAEDHNIYIYYPTSAGGGSQRLFRKIGSRSSVYSPESRVRKTGSFIYEDFMPTDGTDVKVYTVGPDYAHAEARKSPALDGKVERDSEGKEIRYPVILNHSEKLISRKVCLAFKQTVCGFDLLRANGKSYVCDVNGFSFVKNSNKYYDDCAKILGNMILRELTPTLHIPWSVPFQLDDPPIVPTTFGKMMELRCVVAVIRHGDRTPKQKMKVEVRHPKFFEIFEKYDGYKLGHVKLKRPKQLQEILDIARFLLSEIHTKAHAEIEEKESKLEQLKNVLEMYGHFSGINRKVQMKYQPKGRPRGSSSDDTNLAADQPVEPSLVLILKWGGELTPAGRIQAEELGRIFRCMYPGGQGRSDYSGTQGLGLLRLHSTFRHDLKIYASDEGRVQMTAAAFAKGLLALEGELTPILVQMVKSANTNGLLDNDCDSSKYQNLAKGRLHELMQNDREFSKEDRELINPCNSKSITQALDFVKNPVDCCHHVHLLIRELLHIISIKKDDPKTKDAILYHGETWDLMRCRWEKIEKDFSTKSKLFDISKIPDIYDCIKYDLQHNQHTLQYDQAEELYIYAKNLADIVIPQEYGLTPQEKLAIGQGICSPLLRKIKGDLQRNIDEVEDEFMNRLNPHYSHGVASPQRHVRTRLYFTSESHVHSLLTVLRYGGLLNVVTDEQWRRAMDYISMVSELNYMSQIVIMLYEDPTKDPTSEERFHVELHFSPGVNCCVQKNLPPGPGFRPHSHGDNACNVSLQSSDESNPARIEEENDSNSGEEREGKKRGTSGQRSTDRSAERISPAFGFNRLELRSKQFKSKPIPIGAHHTVSGHEAMDLAKRLNEELASHQQQQNQQLRPISPDIRAVTPDCEPRSRSFEQRPTSGVCAKEPDSQVSVSVSASVSSANASTSSRRQRHSIAGQMSYMKMLGFGGFSKKMATSANSLFSTAVISGSSSAPNLRDMITVSSSGFGDVPPIRPLETLHNALSLRKLDSFLQDMILAQIFKTPTGSPPRGFSKNTLPAVSSMTLTASNQTEVVEHEPISTTVTPTFDRRGSESGSTADAHLRLLSESQCPNLDDSNTELRESLAGKMELWPQDIVKAAEDEELNLSELETKPSLDLTMEIMERGVAGIASIQPMNRDSDETMGGGVFLSVCEEQGSGSTCLTPVSFGMDLDLSMVANKGSITLSMEGFDDDEDATLSAATTPSLLADCEPRLESCYCCPSHAEAPPEVPSDDPRFGFALPVRVTQASPEHARPVRRAHDPVSPRIQKQISLFEGNAAMATGQEKTESSGSVGGGAILHASINLPAAGPHHLRQDARLRKFENLTQSTSNSNFPFESNTLKRVPMQTTKDYDNVSHTQSCINLKSGSSGVLGGSPQRQRGSDGGGVGASGVPAESREPTRVHYGRMNSTCCSASASPSPSPGALIVKERFIEPPKRGVVRGYHGKTQSMDADFLFNEFLLLPAMAPAKISFDSSDIDQASDDDSPSSSKQRHA